Hi Heiko, Am Dienstag, den 25.02.2014, 12:46 +0100 schrieb Heiko Stübner: > This implements support for defining reserved areas as subnodes, > to keep the genpool from using these. > > Suggested-by: Rob Herring <robherring2@xxxxxxxxx> > Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx> > Tested-by: Ulrich Prinz <ulrich.prinz@xxxxxxxxxxxxxx> Acked-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> > --- > drivers/misc/sram.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 118 insertions(+), 7 deletions(-) > > diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c > index afe66571..674b0cd 100644 > --- a/drivers/misc/sram.c > +++ b/drivers/misc/sram.c > @@ -24,6 +24,9 @@ > #include <linux/err.h> > #include <linux/io.h> > #include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/list.h> > +#include <linux/list_sort.h> > #include <linux/platform_device.h> > #include <linux/slab.h> > #include <linux/spinlock.h> > @@ -36,14 +39,35 @@ struct sram_dev { > struct clk *clk; > }; > > +struct sram_reserve { > + struct list_head list; > + u32 start; > + u32 size; > +}; > + > +static int sram_reserve_cmp(void *priv, struct list_head *a, > + struct list_head *b) > +{ > + struct sram_reserve *ra = list_entry(a, struct sram_reserve, list); > + struct sram_reserve *rb = list_entry(b, struct sram_reserve, list); > + > + return ra->start - rb->start; > +} > + > static int sram_probe(struct platform_device *pdev) > { > void __iomem *virt_base; > struct sram_dev *sram; > struct resource *res; > - unsigned long size; > + struct device_node *np = pdev->dev.of_node, *child; > + unsigned long size, cur_start, cur_size; > + struct sram_reserve *rblocks, *block; > + struct list_head reserve_list; > + unsigned int nblocks; > int ret; > > + INIT_LIST_HEAD(&reserve_list); > + > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > virt_base = devm_ioremap_resource(&pdev->dev, res); > if (IS_ERR(virt_base)) > @@ -65,19 +89,106 @@ static int sram_probe(struct platform_device *pdev) > if (!sram->pool) > return -ENOMEM; > > - ret = gen_pool_add_virt(sram->pool, (unsigned long)virt_base, > - res->start, size, -1); > - if (ret < 0) { > - if (sram->clk) > - clk_disable_unprepare(sram->clk); > - return ret; > + /* > + * We need an additional block to mark the end of the memory region > + * after the reserved blocks from the dt are processed. > + */ > + nblocks = (np) ? of_get_available_child_count(np) + 1 : 1; > + rblocks = kmalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL); > + if (!rblocks) { > + ret = -ENOMEM; > + goto err_alloc; > } > > + block = &rblocks[0]; > + for_each_available_child_of_node(np, child) { > + struct resource child_res; > + > + ret = of_address_to_resource(child, 0, &child_res); > + if (ret < 0) { > + dev_err(&pdev->dev, > + "could not get address for node %s\n", > + child->full_name); > + goto err_chunks; > + } > + > + if (child_res.start < res->start || child_res.end > res->end) { > + dev_err(&pdev->dev, > + "reserved block %s outside the sram area\n", > + child->full_name); > + ret = -EINVAL; > + goto err_chunks; > + } > + > + block->start = child_res.start - res->start; > + block->size = resource_size(&child_res); > + list_add_tail(&block->list, &reserve_list); > + > + dev_dbg(&pdev->dev, "found reserved block 0x%x-0x%x\n", > + block->start, > + block->start + block->size); > + > + block++; > + } > + > + /* the last chunk marks the end of the region */ > + rblocks[nblocks - 1].start = size; > + rblocks[nblocks - 1].size = 0; > + list_add_tail(&rblocks[nblocks - 1].list, &reserve_list); > + > + list_sort(NULL, &reserve_list, sram_reserve_cmp); > + > + cur_start = 0; > + > + list_for_each_entry(block, &reserve_list, list) { > + /* can only happen if sections overlap */ > + if (block->start < cur_start) { > + dev_err(&pdev->dev, > + "block at 0x%x starts after current offset 0x%lx\n", > + block->start, cur_start); > + ret = -EINVAL; > + goto err_chunks; > + } > + > + /* current start is in a reserved block, so continue after it */ > + if (block->start == cur_start) { > + cur_start = block->start + block->size; > + continue; > + } > + > + /* > + * allocate the space between the current starting > + * address and the following reserved block, or the > + * end of the region. > + */ > + cur_size = block->start - cur_start; > + > + dev_dbg(&pdev->dev, "adding chunk 0x%lx-0x%lx\n", > + cur_start, cur_start + cur_size); > + ret = gen_pool_add_virt(sram->pool, > + (unsigned long)virt_base + cur_start, > + res->start + cur_start, cur_size, -1); > + if (ret < 0) > + goto err_chunks; > + > + /* next allocation after this reserved block */ > + cur_start = block->start + block->size; > + } > + > + kfree(rblocks); > + > platform_set_drvdata(pdev, sram); > > dev_dbg(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, virt_base); > > return 0; > + > +err_chunks: > + kfree(rblocks); > +err_alloc: > + if (sram->clk) > + clk_disable_unprepare(sram->clk); > + return ret; > } > > static int sram_remove(struct platform_device *pdev) regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html